Electrical generator systems in which a renewable energy, such as wind, solar, biomass, etc., is converted to electrical energy through an intermediate storage step are known in the art. For example, U.S. Pat. No. 3,806,733 discloses a wind driven electrical energy conversion apparatus in which the wind energy is converted to a pressurized air supply which is subsequently converted to rotary power by inflating air cells carried by an endless belt immersed in a tank filled with a fluid. The rotary output of the endless belt is connected to an electrical generator which produces the desired electrical power. U.S. Pat. No. 4,229,661 discloses a power plant for a camping trailer in which the wind energy is first converted to a pressurized air supply which is subsequently converted to a rotary output by an air driven turbine. The rotary output of the turbine is connected to a generator which produces the desired electrical power. U.S. Pat. No. 4,447,738 discloses a wind power electrical generator that includes a windmill mounted to a tower, an air compressor connected to the rotary output of the windmill, and an accumulator for storing the pressurized air output of the air compressor to generate a supply of pressurized air. A first air motor receives pressurized air from the accumulator to generate a rotary output, which drives an electrical generator to generate the desired electrical power. A waste air recovery mechanism includes a second air motor, which is driven by the exhaust of the first air motor to produce a rotary output supplementing the wind energy driving the air compressor.
The foregoing prior art systems are inefficient and are not capable of producing electric power on a large scale over a long period of time. Accordingly, there remains a need for a electric power generation system that can convert renewable energy to a long-term non-battery source of stored energy and then use that stored energy to generate electric power on a large scale over a long period of time.